Many methods have been employed to cool electronic equipment during its operation. One of the most commonly used methods is by employing an air blower to force ambient air into an electronic equipment cabinet. The ambient air removes heat from the electronic components as it passes through the cabinet as shown in FIG. 1. Since within the cabinet of an electronic device there exists many obstacles which would effect the ambient air flow, uneven heat removal will occur and hot spots will remain throughout the cabinet. Consequently, the components which are not adequately cooled or reached by the ambient air flow will fail prematurely due to overheating.
One solution to this problem would be to install a larger air blower into the cabinet so that it can force greater quantities of air through the components contained therein. Installation of a larger blower, however, carries with it other problems. It adds additional weight to the electronic system and also consumes larger amounts of energy. These are undesirable characteristics for any electronic system.
Recently, the combination of impinging air cooling cooling and heat sink, as set forth in FIG. 2, has been used to remove heat locally from heat generating integrated circuit (IC) modules. In addition, at times, closed circuit liquid cooling devices are required to remove heat from IC modules such as CPU modules in IBM.RTM. mainframe computers. The present invention provides a more efficient and economical means for cooling IC modules.
It has been proven through experimentation that, for a given flow rate of air, a pulsating flow of air is more efficient in removing heat from a heat transfer surface than a steady air flow. Even though it has been proven that a pulsating flow of air is more effective for cooling, almost all of the existing cooling systems employ devices which use a steady flow of air. The reason for this is that a steady flow of air, although less efficient than a pulsating flow of air, is much more easily attainable than a pulsating flow. Moreover, generally speaking, a pulsating system is more complex and less reliable than that of a steady flow system because conventional pulsating systems require the use of additional moving components therein to generate pulsatile air flow. The presence or requirement of additional moving parts increases the likelihood of malfunction.
The present invention is able to create the desired pulsating air flow without the use of any moving parts or any electronics.